求如何将(y-0.5)^ 2=x^2+y^2-xy化简成y=2+(x-1)+3/[4(x-1)],
1/x-1/y=4,求分式(3x+xy-3y)/(x-2xy-y)
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1,xy=−12
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
x-y=1,xy=2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
.已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知x-y=3,xy=1,求(-2x+2x+3y)-(3xy+2y-2x)-(x+4y+xy)
x(x-1)-(x平方-y)=-3,求x平方+y平方-2xy
1/x-1/y=3,求2x+3xy-2y/x-y
1/x-1/y=2 求(2x+3xy-2y)/(x-xy-y)的值
已知1/x-1/y=3,求(3x+4xy-3y)/(x-2xy-y)的值
已知1/x+1/y=3,求3x-4xy+3y/(x+2xy+y)的值